# 定义了四个函数，分别完成加减乘除
def myAdd(a,b):
    return a+b

def mySubstract(a,b):
    return a-b

def myMultiply(a,b):
    return a*b

def myDivide(a,b):
    return a/b


print(myAdd(3,4))
print(mySubstract(3,4))
print(myMultiply(3,4))
print(myDivide(3,4))
